Keystone is a video projection mapping library for Processing. Currently, it allows you to warp your Processing sketches onto any flat surface by using corner pin keystoning, regardless of your projector's position and orientation. The goal is to eventually expand this library to enable more advanced projection mapping, such as projecting on 3D models or curved surfaces and edge blending of multiple projector screens.

Thank you to the following contributors for features added to Keystone:

• fixed the XML load/save once more (Machiel Veltkamp)
• improved perspective calculation using JAI (Eduardo Moriana)
• fixed the XML load/save functionality (Andres Colubri)
• added manual control for the surface's corners (Daniel Wiedemann)